Page 1 of 4
Mass and Capacity
BEFORE
Now
WHY?
You measured length using
customary and metric units.
You’ll use metric units of mass
and capacity.
So you can analyze water usage, as
in Exs. 27–29.
Perform an experiment to measure mass.
Word Watch
mass, p. 187
gram, p. 187
milligram, p. 187
kilogram, p. 187
capacity, p. 188
liter, p. 188
milliliter, p. 188
kiloliter, p. 188
1 One person in the group holds a pen in
one hand and a paper clip in the other hand.
2 Another person adds paper clips until the first
person feels that both hands hold the
same amount. Record the number of paper clips.
3 Every person in the group takes a turn estimating the
pen’s mass. Find the mean of the group’s results.
4 Based on the mean you found in Step 3, how
many paper clips would you have in your hand
for 10 pens? for 100 pens?
Units of Mass The mass of an object is the amount of matter it has.
The gram (g) is a metric unit of mass. Two other metric units of mass
are the milligram (mg) and the kilogram (kg).
milligram about the
mass of a grain of
sugar
with
Notetaking
As you preview this
lesson, you may want to
review what you learned
about benchmarks for
metric units of length in
Lesson 2.1.
gram about the mass
of a small paper clip
kilogram about the
mass of a book
Grams, milligrams, and kilograms are related to each other.
1 g 1000 mg
EXAMPLE
1
1 mg 0.001 g
1 kg 1000 g
Choosing Units of Mass
An item has a mass of 10.3 kilograms. Is it a dog or a pencil?
Explain.
The mass of a book is about 1 kg, so 10.3 kg is the mass of about 10 books.
The mass of a dog is closest to the mass of 10 books, so the item is a dog.
Lesson 4.7
Mass and Capacity
187
Page 2 of 4
Units of Capacity Capacity measures the amount that a container
WATER
can hold. The liter (L) is a metric unit of capacity. Two other metric
units of capacity are the milliliter (mL) and the kiloliter (kL).
1.0 LITER
ATED
NON-CARBON
SODIUM-FREE
water
Natural spring
.
bottled at the source
d.
Filtered and ozonate
33.8 FL OZ (1 QT 1.8 FL
OZ)
milliliter about the
liter about the
kiloliter about the
capacity of an
eyedropper
capacity of a large
bottle of water
capacity of 5 bathtubs
Liters, milliliters, and kiloliters are related to each other.
1 L 1000 mL
EXAMPLE
2
1 mL 0.001 L
1 kL 1000 L
Choosing Units of Capacity
Tell whether the most appropriate unit to measure the capacity of
the item is milliliters, liters, or kiloliters.
a. bucket
b. teaspoon
Solution
a. The capacity of a bucket is closest to the capacity of a large bottle of
water. You should use liters.
b. The capacity of a teaspoon is closest to the capacity of an
eyedropper. You should use milliliters.
EXAMPLE
Choosing Metric Units
3
Choose an appropriate metric unit to measure the item.
a. mass of an eraser
b. capacity of a bottle of nail polish
Solution
a. The mass of an eraser is much greater than one milligram and less
than one kilogram. So, you should use a gram.
b. The capacity of a bottle of nail polish is much less than one liter or
one kiloliter. So, you should use a milliliter.
Your turn now
the item.
Choose an appropriate metric unit to measure
1. mass of a car
188
Chapter 4
Decimal Multiplication and Division
2. capacity of a thermos
Page 3 of 4
INTERNET
Exercises
eWorkbook Plus
CLASSZONE.COM
More Practice, p. 711
Getting Ready to Practice
Vocabulary Tell whether the measurement is a mass, a capacity, or
a length.
1. 30 mL
2. 15 g
3. 20 mm
Choose an appropriate metric unit to measure the item.
4. mass of a leaf
5. mass of a sofa
6. capacity of a pool
7. Ice Tea You want to determine how much ice tea will fit into a pitcher.
Do you need to know the mass or the capacity of the pitcher?
Practice and Problem Solving
with
Example
1
2
3
Homework
Exercises
16, 17, 19, 20
18, 27
8–15, 21–26
Online Resources
CLASSZONE.COM
• More Examples
• eTutorial Plus
Tell whether the measurement is a mass, a capacity, or a length.
8. 10 L
12. 5.5 g
9. 0.68 kg
13. 2 m
10. 7.5 mm
11. 9.2 mL
14. 80.4 mg
15. 614 cm
16. The mass of an item is 5 kg. Is the item a shoelace, a plate, or a bicycle?
17. Isaac is holding an object that has a mass of 5 grams. Is the object a
book, a nickel, or a feather?
18. Gail is describing an object that has a capacity of 1.9 liters. Is she
describing a refrigerator, a water pitcher, or a cereal bowl?
Mountain Climbing A mountain climber uses
a piece of equipment called a carabiner.
A carabiner is a small metal ring that
attaches to the climber’s ropes.
19. Do you think the mass of a carabiner
should be measured in milligrams, grams,
or kilograms? Explain your choice.
20. Do you think the mass of the climber
should be measured in milligrams, grams,
or kilograms? Explain your choice.
Choose an appropriate metric unit to measure the item.
21. capacity of a sink
22. capacity of a lake
23. mass of a horse
24. mass of a bubble
25. capacity of a glass
26. mass of a kick ball
Lesson 4.7
Mass and Capacity
189
Page 4 of 4
Extended Problem Solving The table shows the
amounts of water a person usually uses for
certain activities.
Activity
27. Explain Are the amounts measured in liters or
milliliters? Explain your choice.
28. How much water do 4 people use if each
person takes 1 shower, brushes their teeth
3 times, and washes their hands 5 times?
showering
brushing
teeth
washing
hands
Water
used
75.7
3.8
3.2
29. How much water is used in a week for 4 people to do the activities
in Exercise 28? How would you express this amount in kiloliters?
Copy and complete the statement.
30. 1000 mg _?_ g
31. 1 kg _?_ g
32. 1 kL _?_ L
33. 6 kL _?_ L
34. 9 g _?_ mg
35. 4 mL _?_ L
Challenge Use a benchmark to estimate the mass of a brick. Then
estimate the number of bricks you would need to equal the mass
of the object. The mass of the object is given.
36. bag of cement; 24 kg
37. sports car; about 1800 kg
Mixed Review
Round the decimal as specified. (Lesson 3.4)
38. 5.976 (nearest tenth)
39. 0.0929 (nearest thousandth)
Evaluate the expression. (Lesson 4.5)
40. 1.26 1000
41. 5.7 100
42. 6.3 0.1
43. 37.4 0.01
Basic Skills Estimate the quotient.
44. 109
8
45. 191
0
5
46. 323
0
5
47. 1029
8
92
Test-Taking Practice
INTERNET
State Test Practice
48. Multiple Choice Which measurement is most likely the capacity of
a fish bowl?
CLASSZONE.COM
A. 0.5 L
B. 3.8 L
C. 7.6 L
D. 20.5 L
49. Multiple Choice The mass of a piece of paper would most likely be
expressed with which unit of measurement?
F. liters
190
Chapter 4
Decimal Multiplication and Division
G. milligrams
H. grams
I. kilograms